A -(65,-35)

You pay $30 each month for satellite TV, plus $2.50 for every movie you purchase. Write and solve an equation to find the number

raketka [301]

The initial payment per month being 30 and each movie being 2.50 means that if the total payment is 45 then you pay for 6 movies per month, 30x+6(2.5x)

7 0

2 years ago

Read 2 more answers

The Information Technology Department at a large university wishes to estimate the proportion of students living in the dormitor

nadya68 [22]

Answer:

$n=\frac{0.5(1-0.5)}{(\frac{0.05}{1.96})^2}=384.16$

And rounded up we have that n=385

Step-by-step explanation:

Previous concepts

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".

The margin of error is the range of values below and above the sample statistic in a confidence interval.

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

Solution to the problem

In order to find the critical value we need to take in count that we are finding the interval for a proportion, so on this case we need to use the z distribution. Since our interval is at 99% of confidence, our significance level would be given by $\alpha=1-0.99=0.01$ and $\alpha/2 =0.005$ . And the critical value would be given by:

$z_{\alpha/2}=-2.58, z_{1-\alpha/2}=2.58$

The margin of error for the proportion interval is given by this formula:

$ME=z_{\alpha/2}\sqrt{\frac{\hat p (1-\hat p)}{n}}$ (a)

And on this case we have that $ME =\pm 0.05$ and we are interested in order to find the value of n, if we solve n from equation (a) we got:

$n=\frac{\hat p (1-\hat p)}{(\frac{ME}{z})^2}$ (b)

We can use as an estimator for p $\hat p =0.5$ . And replacing into equation (b) the values from part a we got:

$n=\frac{0.5(1-0.5)}{(\frac{0.05}{1.96})^2}=384.16$

And rounded up we have that n=385

3 0

3 years ago

How does a person use credit to make a

Black_prince [1.1K]

Answer:

makes a promise to pay at some point in the future

Step-by-step explanation:

Using credit means you borrow money to buy something, which is called a "loan", then you can buy the things you want, and you can pay it back later (with interest).

6 0

3 years ago

Find the dimension of the cube volume = 64

olganol [36]

S
A
=
96
sq in.
Explanation:
V
=
s
3

64
=
s
3

find the cubic root of each side
3
√
64
=
s

4
=
s

so the side of the cube is 4 cu in.
The surface area of a cube is

S
A
=
n
A

where
S
A
is surface area,
n
is the number of faces, and
A
is the area of one face.
Te area of one face (
A
) is
s
2

so
A
=
16

n
=
6
S
A
=
6
⋅
16
=
96

6 0

2 years ago

Cos^4A - sin^4A = COS2A

Elenna [48]

Step-by-step explanation:

hope u understand it's just a simple formula

8 0

2 years ago